The present invention relates to railway freight car trucks and, more particularly, to railway freight car truck sideframes having an improved and strengthened column member.
Railway freight car trucks are usually comprised of a three piece arrangement wherein each truck includes two sideframes laterally spaced from each other. Each sideframe includes a centrally located opening formed by vertical columns. Such centrally located opening is usually referred to as the bolster opening or pocket and is adapted to receive the ends of a bolster extending laterally from and perpendicular to the sideframes. The ends of each sideframe are laterally aligned to receive an axle wheel set in what is usually termed the pedestal jaw of the sideframe.
Typical three piece railway freight car trucks are shown in U.S. Pat. Nos. 4,363,276; 4,838,174; and 5,718,177.
A typical railway freight car truck sideframe is comprised of an elongated top compression member that extends in a longitudinal direction parallel to the railway track. The sideframe also comprises two diagonally extending tension members that extend generally downwardly at an acute angle from near the ends of the top compression member. A bottom member extends longitudinally and joins the lower ends of the diagonal tension members. Column members extend generally vertically between the bottom member and the top compression member from a point near the junction of the diagonal tension members and the bottom member. Such column members form the bolster opening in the sideframe. A top portion of the bottom member of a sideframe is usually referred to as the spring seat of the sideframe as it is adapted to receive the spring group upon which the ends of the bolster are supported. The bolster extends laterally between each sideframe with the ends of the bolster extending into the bolster pockets and supported on a spring group.
It should be understood that the sideframe is an engineered structural member that is largely hollow to accomplish weight saving. It should also be understood that the sideframe is a unitary cast steel structure made in a foundry casting operation. Accordingly, it is possible to strengthen the sideframe by the addition of various supporting structures that would become part of the unitary sideframe. However, such addition of strengthening members is always balanced against the need for lighter weight freight car trucks.
From time to time, certain freight car truck designs exhibit various degrees of decreased performance when exposed to higher capacity service. For example, certain variable damped railway freight car trucks experienced cracking in their sideframe columns when utilized in 125 ton freight car service. Such freight car truck sideframes utilized in general the column support shown in U.S. Pat. No. 4,363,276 wherein a single horizontal support rib provides lateral support for the columns.
Accordingly, it is an object of the present invention to provide an improved and strengthened railway truck sideframe.
It is another object of the present invention to provide a railway truck sideframe having an improved and strengthened column structure thereby particularly providing an improved and strengthened bolster pocket.